# Switch to Protonmail Reason #33: Detect tampering with supported signed contact information

Changing a stored contact detail could redirect a private message or call toward an attacker.

2026-09-09
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Switchboard Tech Services


![Switch to Protonmail Reason #33: Detect tampering with supported signed contact information](https://switchboardtechservices.com/static/images/defaults/guides.webp)

## Why this matters

Changing a stored contact detail could redirect a private message or call toward an attacker. Privacy is easier to defend before this information is collected than after it has spread.

## The protection

Proton supports digital signatures for certain contact details to help detect alteration.

## Take action

Review unexpected contact changes before acting on them. Verify critical contact information independently. Email protection depends on the route and settings. Ordinary mail involving outside providers is not automatically end-to-end encrypted, and email metadata is not universally hidden.

## Sources

[Proton Mail security checklist](https://proton.me/support/new-account-owner-security-checklist).

- Categories:
  [Proton Mail](https://switchboardtechservices.com/guides/categories/proton-mail/)
- Tags:
  [#Digital Self-Defense](https://switchboardtechservices.com/guides/tags/digital-self-defense/), [#Proton Mail](https://switchboardtechservices.com/guides/tags/proton-mail/), [#Email Privacy](https://switchboardtechservices.com/guides/tags/email-privacy/), [#Contacts Privacy](https://switchboardtechservices.com/guides/tags/contacts-privacy/)

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Canonical URL: https://switchboardtechservices.com/guides/switch-to-protonmail-reason-33/

Language: en-us

Content type: guide

Author: Switchboard Tech Services

Published: 2026-09-09T20:29:11+00:00

Description: Why detect tampering with supported signed contact information matters for privacy and security.